434 results about "Surface geometry" patented technology

An acetabular shell liner having a variable rim surface geometry, which improves range of motion of the femoral component within the liner and decreases the incidence of dislocation and subluxation, and methods of making and using the acetabular shell liner. Prosthetic devices, more particularly hip joint prostheses, containing the acetabular shell liner having a variable rim surface geometry are also provided.

A method and system for full-field fringe-projection for 3-D surface-geometry measurement, referred to as “triangular-pattern phase-shifting” is disclosed. A triangular grey-scale-level-coded fringe pattern is computer generated, projected along a first direction onto an object or scene surface and distorted according to the surface geometry. The 3-D coordinates of points on the surface are calculated by triangulation from distorted triangular fringe-pattern images acquired by a CCD camera along a second direction and a triangular-shape intensity-ratio distribution is obtained from calculation of the captured distorted triangular fringe-pattern images. Removal of the triangular shape of the intensity ratio over each pattern pitch generates a wrapped intensity-ratio distribution obtained by removing the discontinuity of the wrapped image with a modified unwrapping method. Intensity ratio-to-height conversion is used to reconstruct the 3-D surface coordinates of the object. Intensity-ratio error compensation involves estimating intensity-ratio error in a simulation of the measurement process with both real and ideal captured triangular-pattern images obtained from real and ideal gamma non-linearity functions. A look-up table relating the measure intensity-ratio to the corresponding intensity-ratio error is constructed and used for intensity-ratio error compensation. The inventive system is based on two-step phase-shifting but can be extended for multiple-step phase-shifting.

An apparatus for delivering or withdrawing a fluid through at least one layer of the skin is provided. The device may include a body having a top face, a bottom face, a side edge and at least one channel. The bottom face includes a first surface area and a second surface area adjacent to and recessed at a first distance from the first surface area. The bottom face further includes at least one raised protrusion disposed on the second surface area. The protrusion has a height from the first surface greater than the first distance. At least one dermal-access member is provided in the protrusion and is in fluid communication with the channel to deliver or withdraw the fluid.

A system, apparatus and method for three-dimensional scanning and digitization of the surface geometry of objects are claimed. The system comprises a hand-held apparatus that is auto-referenced. The system is auto-referenced since it does not need any positioning device to provide the 6 degree of freedom transformations that are necessary to integrate 3D measurements in a global coordinate system while the apparatus is manipulated to scan the surface. The system continuously calculates its own position and orientation from the reflection of a projected laser pattern on an object's surface and 2D positioning features originating from the observation of target positioning features. Using the described system, it is possible to simultaneously build and match a 3D representation of the positioning features while accumulating the 3D surface points describing the surface geometry.

A glenoid component is provided to reduce glenoid loosening when implanted in orthopedic joint replacement/reconstruction, such for a shoulder. The glenoid component can include pegs or a keel and articulating surface geometry that uses complex, non-spherical geometry to recreate a level of constraint that is adequate, but not excessive, to thereby mitigate loosening of the glenoid component after implantation. In addition, some embodiments provide that peak stresses both within cement and at an interface of the cement and a supportive component can be reduced. Further, geometry of the pegs can allow stresses to be evenly applied to a cement mantle formed in the supportive component. Finally, the pegs can be configured to desired lengths in order to avoid placement in areas of the supportive component, for example, that have insufficient bone stock.

A torsional dissection tip and method of use comprising a longitudinal-torsional resonator having a cutting surface at a distal end with cutting teeth of a pitch optimized to the torsional or longitudinal displacement of the distal tip. The present art apparatus and method of use utilizes uniquely designed cutting surface geometries with the aforesaid pitch attributes for surgical applications. Utilization of the present art torsional dissection tip allows a surgeon to easily remove hard tissues such as bone without moving the present art instrument to any site except that which is to be dissected.

The influence of surface geometry on metal properties is studied within the limit of the quantum theory of free electrons. It is shown that a metal surface can be modified with patterned indents to increase the Fermi energy level inside the metal, leading to decrease in electron work function. This effect would exist in any quantum system comprising fermions inside a potential energy box. Also disclosed is a method for making nanostructured surfaces having perpendicular features with sharp edges.

A method for a short-term prediction of future ship motion in open water to furnish visual cueing information that can be remotely presented to a pilot during an aircraft landing is described. Two sets of samples of the sea surface geometry along a radial azimuth line from a ship as a function of elevation of a sensor are first acquired. These are compensated to remove the components due to the ship's motion. Two wave traces are then separately derived in Cartesian format from the two sets of acquired samples. These wave traces are subjected to a Fast Fourier Transform to detect the amplitudes and phases of the individual wavelength components. The direction of the wavelength components is determined using a measure of their phase change in the scan direction during the time interval between the two scans together with their measured wavelength. The amplitude, direction and phase of each component is utilized together with the known motion characteristics of the moving ship in order to derive a short-term prediction of future ship motion in the time domain. A quiescent period of the ship motion is located by comparing the short-term prediction with the pre-defined operating limit criteria. Finally, a message signal is transmitted to the pilot of the aircraft indicating Time-to-Land and the duration of the quiescent period.

A three-dimensional object is manufactured by forming a series of three-dimensional formed curves of extruded material that together comprise the geometry of the surface of the object. The material is extruded from a nozzle that is positioned by a robotic arm under the control of a robotic controller. A computer that has a definition of the geometric surface generates commands to the robotic controller to cause it to sequentially form the series of formed curves that the computer calculates comprise the surface geometry.

A workpiece authentication system uses shape recovery techniques to extract explicit three dimensional (“3-D”) features of the surface geometry of the designated portion of a workpiece from images produced using different lighting conditions. The system then bases authentication on the 3-D surface features. The system recovers surface normals, or equivalently gradients, for selected locations within a designated portion of the workpiece from multiple enrollment images produced under different illumination conditions. The system then encodes the surface normal information into authentication indicia that is placed on the workpiece and/or stores the surface normals or related information. Thereafter, the system determines that a given workpiece is authentic if the surface normals recovered from various verification images correspond to the stored surface normal information or the surface normal information encoded into the indicia. Alternatively, the system may use the surface normals to predict what an image should contain when the workpiece is subjected to a particular lighting condition. The system then determines that the workpiece is authentic if the predicted image and the image produced using the workpiece correspond. The system may instead encode brightness patterns associated with one or more enrollment images into the indicia. The system then recovers surface normals from images produced during verification operations, predicts what the brightness image should contain and compares the enrollment image to the prediction.

A method of modifying the apparent wettability (the area contacted by a liquid) of solids with liquids by controlling the surface geometry or the capillary geometry. This modification is possible by understanding the geometric relationship between the contact angle and the included angle of surface features. This same geometric relationship can be used to control entrance of a liquid into a capillary and the flow of more than one fluid in distinct streams through a capillary device.

There is provided an acetabular shell liner, and particularly a constrained liner, having a variable rim surface geometry to improve the range of motion of a femoral component within the liner and decrease the incidence of dislocation and subluxation. There are also provided methods of making and using the acetabular shell liner. Prosthetic devices, and particularly hip joint prostheses, containing the acetabular shell liner having a variable rim surface geometry are also provided.

A drill bit has cutting elements with multiple cutting surface geometries that are positioned so that their cutting profiles overlap, but do not completely contain or engulf one another. The different cutting surface geometries and the specific overlap create a zone of high density in the middle regions of the cutting profiles and low density in the periphery, resulting in a cutting profile that becomes sharper with increasing wear. Such an arrangement is more effective and stable as the drill bit encounters hard and abrasive formation materials. Moreover, cutting elements with larger axial volumes may be combined with cutting elements having smaller axial volumes, resulting in an even more effective drill bit in terms of durability and ability to drill efficiently in hard and abrasive formations.

An improved biometric data sensing circuit, for example adapted for fingerprint sensing, uses a charge subtraction technique at the input of the circuit integrator to cancel the so called “common mode” signal from the circuit output. The result is an output signal that is (a) linear, (b) free from any amplification effect due to the presence of the detected object (e.g. a finger), and (c) indicative of the detected object's fine surface geometry (i.e., indicative of the fingerprint's ridges and valleys).

A method of producing at least one of microscopic and submicroscopic particles includes providing a template that has a plurality of discrete surface portions, each discrete surface portion having a surface geometry selected to impart a desired geometrical property to a particle while being produced; depositing a constituent material of the at least one of microscopic and submicroscopic particles being produced onto the plurality of discrete surface portions of the template to form at least portions of the particles; separating the at least one of microscopic and submicroscopic particles comprising the constituent material from the template into a fluid material, the particles being separate from each other at respective discrete surface portions of the template; and processing the template for subsequent use in producing additional at least one of microscopic and submicroscopic particles. A multi-component composition includes a first material component in which particles can be dispersed, and a plurality of particles dispersed in the first material component. The plurality of particles is produced by methods according to embodiments of the current invention.